Astronaut Edwin E. Aldrin Jr., lunar module pilot, poses for a photograph beside the deployed United States flag during Apollo 11’s extravehicular activity on the lunar surface. This picture was taken by mission commander Neil A. Armstrong.

Photo: NEIL A. ARMSTRONG, MBR / TNS

If space is the final frontier, this country is doing a poor job charting a course to the outer limits. This year America celebrates the 50th anniversary of Neil Armstrong taking the first step by a human on the moon, and no one knows when we will go back. Not to mention reach another planet.

The Chronicle’s ongoing series, “Mission Moon,” provides a compelling account of the level of commitment it took for this country to send Apollo 11 to the moon in 1969. Who knew three years later, when Gene Cernan stepped off the moon, that it would take decades for us to return? Blame it on the mixed messages NASA has received from different presidents over the past 50 years.

The space agency’s mission was clear in 1961 when President John F. Kennedy boldly declared, “I believe we should go to the moon.” Kennedy’s goal was accomplished in less than 10 years. It’s a shame he didn’t live to see it. NASA has tried to stay on course despite three horrific tragedies since Kennedy was assassinated in 1963.

The next year, President George W. Bush announced the shuttle program would be shut down once it finished transporting modules in low orbit to construct the International Space Station. Bush also announced NASA would begin a new program called Constellation to build a vehicle capable of deep-space missions. Constellation, however, was axed in 2010 by President Barack Obama, who cited the project’s mushrooming cost and inefficiency. Obama directed NASA to instead build a new Space Launch System capable of reaching Mars by the 2030s.

The shuttles were grounded in 2011. Six years later, Obama was out and NASA was taking orders from President Donald Trump, who now wants to cut funding for the over-budget, off-schedule SLS project and instead go back to the moon. In a recent speech at the U.S. Space & Rocket Center in Huntsville, Ala., Vice President Mike Pence challenged NASA to “return an American astronaut to the moon in the next five years.”

NASA administrator Jim Bridenstine didn’t back down from the challenge, but during a town hall meeting in Washington he said NASA needs more money to achieve it. He’s right. NASA received $5.2 billion, or about 5 percent of a much smaller federal budget, when Kennedy directed it to put a man on the moon. Adjusted for inflation, that’s the equivalent to more than $43 billion today. By contrast, the $21 billion Trump has proposed for NASA next fiscal year is only about 0.5 percent of the federal budget.

Pence suggested in Huntsville that money isn’t the issue. He accused the space agency of “bureaucratic inertia” and “paralysis by analysis” and warned that, “If commercial rockets are the only way to get American astronauts to the moon in the next five years, then commercial rockets it will be.”

It’s true that commercial companies have assumed a huge role in space exploration. Joining familiar aircraft contractors such as Boeing, Lockheed and Northrop Grumman are new companies that include SpaceX, founded by Elon Musk, and Blue Origin, founded by Jeff Bezos. Amid so much change, it’s important for Washington to chart a course for NASA’s future that won’t be so easily shelved every time someone new is in the White House. Nor should its funding be tied to whichever congressional district the appropriation will benefit.

NASA’s role is evolving in this brave new world where entrepreneurs hope to send manned rocket ships into the unknown; the question is whether it is evolving quickly enough.

Space historian Jim Oberg, a former mission controller at the Johnson Space Center, says the private space companies remind him of the old Apollo teams that included experts from various scientific, mathematical and engineering disciplines. “NASA today is more educationally homogeneous; they’re not as imaginative,” Oberg told the editorial board. He added, however, that “it’s unfair to criticize NASA for what the government has made it.”

Good point. Too often politics and changing presidential priorities have limited the space agency’s options.

It’s clear it that NASA must continue working closely with private companies. Their teamwork will create a much larger knowledge base and could drive down costs. Beyond that, NASA must be given the support it needs, free of parochial politics and presidential inconsistency, to make the next half-century of space exploration and travel as inspirational as the last.